1. Field of the Invention
The present invention relates to a system for providing information on quality and reliability and, more particularly, to a system for providing information on the quality and reliability of an optical semiconductor device. The present invention achieves this by utilizing a communication network which controls and efficiently manages quality and reliability.
2. Related Background Art
In a conventional method for ensuring the quality and reliability of an optical semiconductor device, such as a semiconductor laser diode or a light emitting diode, a maker who produces the device uses data on the device obtained by inspection during production thereof and at the time of delivery to ensure the quality and reliability of the device, as shown in FIG. 1. On the other hand, a user who uses the device ensures the quality and reliability of an entire product incorporating the device by making an acceptance inspection of the device and a delivery inspection of the product incorporating the device. That is, the maker and the user respectively manage different data and methods to ensure the quality and reliability of their products.
On the contrary, devices, such as optical semiconductor devices, gradually degrade after production. Such devices degrade at different rates due to variations in production conditions. The rate of degradation of the devices will increase with the lapse of time if a production fault occurs or if the devices receive stress after production. In a case where the above-described conventional method is applied to such devices, it is not possible to compare the condition of the device when a product incorporating the device is delivered with the initial condition of the device. Also, the definition of an optical semiconductor device as a good product is so broad that there is a possibility that a product whose quality and reliability are uncertain may be recognized as a good product with reference to the delivery specifications.
An object of the present invention is to solve the above-described problems of the prior art with a system for providing quality and reliability information which is capable of accurately obtaining a condition of an optical semiconductor device at the time of delivering a product incorporating the device.
Another object of the present invention is to provide a system for providing information on quality and reliability, comprising: a first information communication terminal for outputting, as information on the side of a maker producing an optical semiconductor device, at least one of information on a characteristic of the device in a production step, information on the characteristic of the device before an aging step, information on the characteristic of the device after the aging step, and information on the characteristic of the device in a delivery inspection step of the device; a second information communication terminal for outputting, as information on the side of a user using the device, at least one of information on the characteristic of the device in an acceptance inspection step, information on the characteristic of the device in an inspection step when a product incorporating the device is assembled, and information on the characteristic of the device in an inspection step at the time of delivering the product; a communication network for transmitting the information outputted from the first and second information communication terminals; and an information processing apparatus connected to the first and second information communication terminals through the communication network, wherein the information processing apparatus computes a rate of change in the characteristic of the device from the steps on the maker side to the steps on the user side on the basis of information outputted from the first and second information terminals, and outputs a signal for representing an abnormality to at least one of the first and second information terminals through the communication network when the computed rate of change is out of a predetermined numerical range.
Still another object of the present invention is to provide a system for providing information on quality and reliability, comprising: a first information communication terminal provided on the side of a maker producing an optical semiconductor device; a second information communication terminal provided on the side of a user using the optical semiconductor device; a communication network; and an information processing apparatus connected to the first and second information communication terminals through the communication network, wherein the information processing apparatus comprises storage means for storing, as information on the side of the maker producing the device, maker-side information including at least one of information on a characteristic of the device in a production step, information on the characteristic of the device before an aging step, information on the characteristic of the device after the aging step, and information on the characteristic of the device in a delivery inspection step of the device, and for storing, as information on the side of the user using the device, user-side information including at least one of information on the characteristic of the device in an acceptance inspection step, information on the characteristic of the device in an inspection step when a product incorporating the device is assembled, and information on the characteristic of the device in an inspection step at the time of delivering the product; computation means for computing a rate of change in the characteristic of the device from the steps on the maker side to the steps on the user side on the basis of maker-side information and user-side information read out from the storage means, and for outputting a signal for representing an abnormality when the computed rate of change is out of a predetermined numerical range; and communication means for transmitting the signal for representing the abnormality outputted from the computation means to at least one of the first and second information communication terminals through the communication network.